Question

15 ,10 5,……….. in this A.P sum of first 10 term is…….​

Answer 1

Answer:

Hello✌️✌️✌️

Step-by-step explanation:

a = 15

d = 10 - 15 = -5

Sn = n/2 (2a + (n - 1)d)

Sn = 5 * ( 30 - 5*9)

Sn = 5 * (30 - 45)

Sn = 5 * (-15)

Sn = - 75

Answer 2

Answer:

t10=-35

Step-by-step explanation:

A.P 15,10,5..........

a=15

t1=15, t2=10, t3=5

d=t2-t1

=10-15

=-5

d=-5

n=10

t10=a+(n-1)d

=15+(10-1)-5

=15+(-50+5)

=15-45

=-35

t10= -35